The best software to edit and protect your documents
I recommend using Adobe Acrobat DC since it is a software with many tools to edit and mix documents. I recommend using the premium version because it allows saving documents in the cloud and thus be able to access from anywhere.
Adobe Acrobat is a software with many utilities, one of them is the edition of scanned documents, this tool is very useful since I am continually creating documents with forms. Adobe Acrobat DC allows me to add signatures to all my documents and protect them so that nobody else can edit them, another tool of many help is the option to combine files, you can combine, images of various formats, other PDF files, among others.
There is only one thing that adobe acrobat should improve and that is when you edit scanned documents, although it recognizes the letters clearly, it needs to recognize the spaces for example in the tables of forms and lines.